What Do You Think Of Social Media? (facebook, Youtube, Yahoo!answers, Etc)?

I am in the process of writing an essay on social media for my university course, but am needing some quotes by users of some socializing sites - in this case, socializing means where one person can write/speak to another person using the technology of the Internet.
I am looking for a few positive remarks, and few negative remarks, so if anyone could write a small paragraph, or a sentence on their thoughts, I would be greatly appreciative.
I will give the best answer to the most helpful, and properly written quotes, eg, BAD: it is gud GOOD: I think that networks such as MySpace are a brilliant way of being able to communicate with some old friends I never thought I'd talk to again.
Thanks to everyone who replies, in advance.